Flexible curtain construction



April 1969 L. F. SCHROEDER 3,437,126

FLEXIBLE CURTAIN CONSTRUCTION Filed July 19, 1967 IN VEN TOR. 45m A saw/eons;

United States Patent Oflice 3,437,126 Patented Apr. 8, 1969 US. Cl. 160-235 11 Claims ABSTRACT OF THE DISCLOSURE This disclosure relates to a flexible curtain construction in which a plurality of relatively inflexible slats, prefer ably made out of metal, are interconnected in such a way so as to permit relative rotation of each slat with respect to adjacent slats about a longitudinal axis. Each slat has a projecting lug extending substantially perpendicular to the plane of the slat surface, and a longitudinal engaging slot at an opposite longitudinal edge thereof, such that each projecting lug is inserted into the slot of an adjacent slat. The projections are L-shaped, and an edge of the projection is bent in order to lock the projection into the slot. The projecting lug and the slot containing surface are preferably positioned on flanges extending substantially perpendicular to the plane of the slat.

This invention relates to a flexible curtain construction in which a plurality of relatively inflexible slats are interconnected in such a way as to permit relative rotation of each slat with respect to adjacent slats about a longitudinal axis, in which construction the slats are interconnected by means of flat projecting lugs extending at an angle to the plane of the slats, which lug-s lock into the slots in adjacent slats.

In another of its aspects, the invention relates to a flexible curtain construction as hereinbefore described, wherein each slat has at least one projecting lug at a longitudinal edge and a longitudinal engaging slot at an opposite longitudinal edge thereof.

In still another aspect, the invention relates to a flexible curtain as has been hereinbefore described, wherein each projecting lug is positioned on an edge of a first longitudinal flange which extends at an angle to the plane of the slat, the engaging slot is positioned on a surface, spaced from the plane of the slat and connected by a second longitudinal flange positioned at an angle to the plane of the slat, whereby the sum of the angles between the first flange and the slat, and the angle between the second flange and the slat is about 180.

In still another aspect, the invention relates to a flexible curtain construction, as hereinbefore described, wherein the projecting lug is L-shaped, and a laterally extending portion of the lug is bent to lock the lug into the engaging slot.

It has long since been recognized that it is desirable to use flexible curtains made of metal, for example, for cabinets, safes, and like cases, to hold papers, files, and other valuables which are to be protected from theft or injury, and yet are easily accessible.

For example, McKenzie, in U.S. Patent No. 538,430, patented Apr. 30, 1895, discloses a flexible metal curtain construction in which a plurality of metal slats having abutting flange portions which ride in a track are interconnected by a wire passing through the slats.

Fogelquist, 1,396,414, patented Nov. 8, 1921, discloses a flexible door construction in which each slat has a longitudinal edge folded inwardly and upwardly on itself, and then bent inwardly and downwardly, and then again upwardly to form a receiving area at one edge of the flange. The other edge is folded inwardly and downwardly to engage the receiving edge of adjacent slats.

Many other door constructions are well known. For example, it is known to provide a hinge type pin and knuckle joint to attach adjacent slats in a flexible metal curtain. It is also known to employ interlocking rounded beads at the edge of the slats to attach the metal slats together.

I have now discovered a flexible door construction in which interlocking slats are employed and the slats are connected with the use of a simple projecting lug and an engaging slot on adjacent slats. Preferably, the projecting lug is positioned at an edge which is substantially perpendicular to the plane of the slats and the slot is in a flange portion of the other longitudinal edge of the slats spaced from the plane of the slat.

By various aspects of this invention, one or more of the following or other objects can be obtained.

It is an object of this invention to provide an improved flexible metal curtain which is simple in construction and easily assembled.

It is a further object of this invention to provide a novel curtain construction in which relatively inflexible slats are interlocked such that each slat is rotatable about a longitudinal axis with respect to the other.

It is still a further object of this invention to provide a novel metal curtain construction in which each slat is easily manufactured and the curtain is easily assembled.

It is yet another object of this invention to provide a novel, flexible metal curtain construction in which each of a plurality of interconnected slats are employed, whereby the means for connecting the slats are not visible from the outside of the curtain.

Other aspects, objects, and the several advantages of this invention are apparent to one skilled in the art from a study of this disclosure, the drawings, and the appended claims.

According to the invention, there is provided a flexible curtain construction in which a plurality of relatively inflexible slats are interconnected in such a way as to permit relative rotation of each slat with respect to adjacent slats about a longitudinal axis, in which the slats are interconnected by means of flat projecting lugs extending at an angle to the plane of the slats and slots in adjacent slats are provided for engaging the projecting lugs.

Preferably, each projecting lug is positioned on an edge of a first longitudinal flange which extends at an angle to the plane of the slats, and each engaging slot is positioned on a surface parallel to the plane of the slat, and spaced from the plane of the slat, and connected by a second longitudinal flange bent at an angle to the plane of the slat. The angles between the first flange of the slat, and the second flange and the slat are such that when the two flanges are adjacent one another, and parallel to one another, the plane of each slat is parallel. Preferably, each longitudinal flange is perpendicular to the plane of the slat.

The invention will now be described with reference to the accompanying drawings in which:

FIG. 1 is a perspective view of a cabinet with a flexible metal curtain of the invention;

FIG. 2 is a perspective view of a slat employed in the curtain of FIG. 1;

FIG. 3 is a sectional view of a curtain according to the invention, showing the interengagement of the slots and projections;

FIG. 4 is a perspective view of an assembled section such as shown in FIG. 3;

FIG. 5 is a sectional view through VV of FIG. 2; and

FIG. 6 is a sectional view through VI-VI of FIG. 2.

Referring now to the drawings, a cabinet 2 is provided with a flexible curtain 4 made up of slats and having a handle member 6. The flexible curtain slides in a track (not shown) to roll the curtain back within the top portion of the cabinet.

Each slat has a flat outer surface 11, and at one edge thereof, is bent inwardly to form a first flange 12 having at the edge thereof, a projecting lug 14. The projecting lug is relatively flat and L-shaped, having a laterally extending portion 16. The lug 14 is provided with bevelled surfaces 18 and 20 to facilitate assembly of the slats.

At the other longitudinal edge of the slat, there is an inwardly extending flange 22 and an upwardly extending flange 24, which flange 24 is substantially parallel to the plane of the slat 11. The upwardly extending flange 24 is provided with longitudinal slot 26, which is adapted to engage a projecting lug of an adjacent slat, as shown more clearly in FIG. 3. A portion of the slot is positioned in flange 24 and a portion is in flange 22. For example, the slot thickness in each flange can be about of an inch. Preferably, after the lugs have been inserted into the slots of adjacent slats, the laterally extending portion 16 of each projecting lug is bent downwardly to lock the projecting lug in the engaging slot. Obviously, the laterally extending portion 16 could also be bent upwardly to lock the projecting lug into the slot. As can be seen from the drawings, the width of flange 12 is approximately equal to the width of flange 22. For example, the width of these flanges can be about of an inch. The angle between the slat and flange 12, and the angle between the slat and the flange 22 can be varied so long as the sum of the angles add up to 180. In this manner, the outer surfaces of the slats will be parallel and form a flat surface when flange 12 of one slat is in contact with and parallel to a flange 22 of an adjacent slat.

By the use of the invention the slats can have a rotational angle of about 90 with respect to each other. In the preferred embodiment of the invention, the slats are made of metal, such as steel or aluminum. Other materials, such as plastic, however, can also be employed and are within the scope of the invention.

Whereas the invention has been described with reference to a slat having a projecting lug at one longitudinal edge thereof, and a slot at an opposite longitudinal edge, it is within the scope of the invention to provide other arrangements of slots and projections. For example, alternate slats can have projecting lugs at each of the longitudinal edges and alternate slats can have longitudinal slots to engage the projections in the adjacent slats.

Also, it is within the scope of the invention to provide on one longitudinal edge, a projecting lug and a longitudinal slot, and on the other edge of the slat, a longitudinal slot opposite the projecting lug, and a projecting lug opposite the longitudinal slot on the other longitudinal surface. Other arrangements of slots and projecting lugs will be obvious to those skilled in the art.

Whereas, in the description of the invention there has been shown only one projecting lug and one engaging slot on each slat, it is obvious that a plurality of slots and engaging lugs can be provided on each slat. Preferably, two or three projecting lugs and slots are employed on each slat.

The slats are easily made with a minimum of operations and easily assembled. The slats can be stamped from a flat metal sheet to form a pattern in which the projecting lug 18 and the slot will be cut out. The flange 12 is bent inwardly to form one portion of the slat, and the flanges 22 and 24 are bent accordingly to complete the slat construction. The slats are easily assembled by placing a projecting lug 18 in a corresponding slot 26 of an adjacent ,4 slat, and bending laterally extending portion 16 downwardly.

I claim:

1. In a flexible curtain construction in which a plurality of relatively inflexible flat slats are interconnected in such a way as to permit relative rotation of each slat with respect to adjacent slats about a longitudinal axis, each slat rotating in the same angular direction, the improvement which comprises: each joint between adjacent .slats comprising at least one flat lug on one longitudinal edge of one slat, the plane of said lug being angularly disposed relative to the plane of said one slat; and a longitudinal flange on an adjacent slat, said longitudinal flange extending at an angle to the plane of said adjacent slat; a longitudinal slot formed in said flange, said slot being laterally offset from the plane of said adjacent slat, said flange and said lug being directed so that said lug is engageable with said slot while said one slat and said adjacent slat are parallel; and said lug being engageable in said slot.

2. A flexible curtain construction according to claim 1, wherein each slat has on one longitudinal edge, at least one projecting lug, and a flange containing a longitudinal engaging slot at an opposite longitudinal edge of said slat.

3. A flexible curtain construction according to claim 2, wherein each projecting lug is positioned on an edge of a first longitudinal flange, which extends at an angle to the plane of the .slat, at least a portion of said engaging slot is positioned on a surface spaced from the plane of said slat, and connected by a second longitudinal flange positioned at an angle to the plane of the slat such that the sum of the angles between the first flange and the slat, and the second flange and the slat is about 180, whereby when said curtain is assembled with the plane of said first and second flanges parallel, the plane of each slat will be parallel.

4. A flexible curtain construction according to claim 3, wherein the width of said first flange is equal to the width of said second flange.

5. A flexible curtain construction according to claim 4, wherein each projecting lug is a flat L-shaped member attached at one end to said first flange and extending inwardly and laterally of said slat.

6. A flexible curtain construction according to claim 5, wherein the outer corners of said projecting lugs are bevelled to facilitate assembly of said curtain construction.

7. A flexible curtain construction according to claim 6, wherein said laterally extending edge of said lug is bent to lock said lug into said slot.

8. A flexible curtain construction according to claim 1, wherein each projecting lug is a flat, L-shaped member extending inwardly and laterally of said slat, and when assembled, the laterally extending portion of said lug is bent to interlock said projecting lug in said slot.

9. A flexible curtain construction according to claim 1, wherein the angle of said lug with the plane of said slat is substantially 10. A flexible curtain construction according to claim 1, wherein each of said slats is a metal slat.

11. A flexible curtain construction according to claim 3, wherein a portion of said engaging slot is positioned on said second longitudinal flange.

References Cited UNITED STATES PATENTS PETER M. CAUN, Primary Examiner. 

